Means for fixing tappets to the stems of stamp-mills.



PATENTED MAY 2, 1905.

H. 0. FISHER. MEANS FOR FIXING TAPPETS TO THE STEMS 0P STAMP MILLS.

APPLICATION FILED FEB. 10, 1904.

LodL Patented May 2, 1905.

PATE rr-icE.

HUBERT CHARLES FISHER. OF JOHANNESBURG, TRANSVAAL, ASSIGNOR OF 'ONE-HALF TO GEORGE OSLER SMART, ()F GERMISTON, TRANS- VAAL.

MEANS FOR FlXlNG TAPPETS TC) THE STEIVIS OF STAMP- MILLS.

SPECIFICATION forming part of Letters Patent No. 788,896, dated May 2, 1905.

Application filed February 10, 1904. Serial No. 192,963.

1/) (ti/Z 1071,01, t vii/my concern:

Be it known that I, HUBERT CHARLES FIsHER', a subject of the King of England, residing at Johannesburg, Transvaal, have invented certain new and useful Improvements in Means for Fixing the Tappets to the Stems of Stamp- Mills, (for which I have made application for patent in the Transvaal, No. 387. dated September 11, 1903,) of which the following is a specification.

This invention relates to means for fixing the tappets to the stems of stam p-mills. It is designed with the object of obtaining increased strength in the tappet and the means or devices employed for fixing the same to the stem to prevent the tappet slipping on the stem and also to admit or allow of any desired adjustment of the tappet being effected with greater facility than at present and at the expenditure of much less labor.

In accordance with the present invention a longitudinally-tapered slot or gibway (or slots or gibways) is formed in the bore of the tappet, in which gibway is arranged a gib operated by means of a key located in a transverse slot formed through the tappet and intercepting the gibway at the lower end, so that as the key is driven inward it forces the gib upward until it projects into the bore of the tappet and engages the stem cl the stamp. The wall or bore of the tappet opposite the gibway is grooved to insure the stem being gri 'n'ied between the gib and tappet. In the face of the tappet and in the end of the gibway a driftway is formed which serves for driving the gib downward to release the tappet from the stem.

The invention will be described in detail by aid of the accompanying sheet of drawings, wherein Figure 1 is asectional elevation. Fig. 2 is a plan. Fig. 3 is a sectional elevation at right angles to Fig. 1. Figs. 4, 5, and 6 are front, side, and end elevations, respectively, of the gib B. Figs. 7 and 8 are plan and side elevation, respectively, of the key D.

The tappet A is constructed with the usual longitudinal and central hole a, through which the stamp-stem (not shown in the drawings) is projected.

In the interior or bore of the tappet A two 5 longitudinally-tapered recesses or gibways Z) 7/ are formed. The gibways 7) b are tapered in opposite directions and are located diamet rically opposite each other. The gibways I) 7/ terminate inside the bore at the points 0 c, respectively, and extend to the two opposite ends or faces a a" of the tappet A. Two transverse keyholes d d are formed through the tap pet A, intercepting the gibwaysi) b at their inner and larger ends. The bottoms of the keyways (Z d (see Figs. 1 and 3) are preferably inclined to the plane of the longitudinal axis of the tappet, while the tops of the keyways are normal to said plane and pass through the sides 01" the tappet A, as shown in Figs. 5 2 and 3.

The bore of the tappetis grooved beyond the inner ends of the gibways I) b, as shown at a, which results in a better grip of the stem being obtained when the tappetis lixed. The groove 7 is made the same width as the gibways.

In the gibway Z a gib B is placed, whose inner edge is parallel with the longitudinal axis of the tappet and projects beyond the inside wall of the tappet A and engages the stem to secure the tappet in position thereon. The back of the gib B is tapered to correspond with the gibway in which it fits, so that as it is moved upward it is thereby forced inward to grip the stem and when forced in 30 the opposite direction it releases the stem, and so allows the tappet to be adjusted on the stem or removed therefrom, as may be desired. The inner edge of the gib ll, which projects beyond the walls or bore of the tappet, is 5 curved, as shown at b, to [it the stem.

In the transverse keyway (Z is placed a c0rrespondingly-tapered key D, which when in position engages the larger end of the gib B and operates when moved in one direction to 9 drive the gib B upward in the gibway b to secure the tappet A on the stem. In the ends of the gibways Z) 7/ in the faces rt a of the tappet A are formed driftways c 0 which are provided to admit of the introduction of a drift to drive the gibs B downward to release the tappet from the stem when desired.

In the drawings the gib B is shown located in the gibway b, and when the parts are so arranged the end (i constitutes the working face. One gib B and key D only are employed to fix the tappet A, and the other gibway b and keyway cl are used when the tappet A is inverted to present the other end a" for the working face.

It is preferred to construct the tappet as shown and described with two diametrically opposite gibways tapered in reverse directions, as by this means the tappet may be reversed when worn at one end. It will be obvious that one such gibway may be formed in the bore of the tappet and the tappet be renewed when worn on the one face. If constructed with only one gibway, the bore of the tappet opposite the gibway will be grooved for the full length of the tappet.

In fixing the tappet the gib B is placed in the gibway Z) and the key D in the keyway (Z, and the tappet A then arranged in the desired position on the stem. The key D is then driven in to force the gib B upward. and so secures the tappet. To remove and reverse the tappet A, the key D is first released by being driven in the contrary direction and the drift then projected down the driftway 6 until it engages the top of the gib B. The drift is then hammered, and forcing the gib B downward it releases the stem. If the tappet is constructed to be reversed, the tappet is inverted, and the gib B and key D are then arranged in the opposite gibway 6 and keyway (Z, respectively, and the key D driven inward, thereby securing the tappet in the manner previously described.

It will be understood that by the construction described thetappet is fixed to the stem by means of the one key, whereas with the present arrangement for fixing the tappets two and three keys are usually employed.

What I claim as my invention, and desire to protect by Letters Patent, is'

1. In means for fixing the tappets to the stems of stamp-mills, the tappet constructed with two diametrically opposite gibways in the bore thereof tapering inward toward opposite ends or faces, and with two transverse keyways intersecting the gibways at their larger ends, the bore of the tappet being grooved beyond the larger ends of the gibways, a gib arranged in one of the gibways and a taper-key arranged in the keyway at the larger end of said gibway to serve as a means for moving the gib upward and inward in the gibway to engage the stamp-stem to secure the tappet, substantially as described.

2. In means for fixing the tappets to the stems of stamp-mills, in combination, the tappet A constructed with two diametrically opposite gibways 6?) in the bore thereof tapering inward toward opposite faces or ends a a of the tappet and grooved at e or beyond the inner ends of the gibways and with the transverse keyways (Z d intersecting the gibways at the larger ends and passing through the sides of the tappet, the gib B arranged in one of the gibways constructed with the curved edge 72 projecting into the bore of the tappet to engage the stem, the key D arranged in the keyway cl below the gib B and engaging the larger end thereof and adapted to force the gib upward and inward to grip the stem, the driftways e a formed in the ends or faces rt (4 of the tappet and in the outer ends of the gibways to admit of the insertion of a drift to force the gib downward to release the tappet, substantially as described.

In witness whereof I have hereunto set my hand, in the presence of two subscribing witnesses, this 17th day of December, 1903.

HUBERT CHARLES FISHER.

Witnesses CHAS. ()VENDALE, R. OVENDALE. 

